Non working ABS - Need assistance with troubleshooting

I have a 99 KW with a 2007 flatbed and the ABS doesn't appear to be working on the TRAILER only.
The ABS light is not lit nor do I hear any of the relays click when I initially turn the tractor key to "ON".
I have a brand new elec ABS coil wire.

It seems like there is no power reaching the WABCO module in the trailer.

I had some questions:
How and what is the best way to begin troubleshooting this?
How does the power get to the outlet on the rear of the tractor?
Is it a relay or simple fuse and what might it be labeled?
What pin or color is the standard for the 7-way connector for ABS power into the trailer?

The Tractor ABS works perfectly and has no alarms and passes all of the startup tests.

-JD

 

Bingo. I have NO power on the blue wire (Center pin on the 7 pin plug).

I cant find a fuse labeled as such though in the KW panel.....they are all circuit breakers but that doesnt mean they are all good of course..

-JD

 

I dont see anything like that BUT there are several ACC or BATT ones that have nothing else defined in them.
So its hard to tell other than checking each ACC fuse. I do see trailer hot-line and it has no fuse in it but adding
one didnt do a darn thing...

 

Mine is a 99. I think in 98 forward they did a center pin hot with the key.
I dont have a dash switch for a trailer but there likely could be a wire inside the dash (unused) as there are many
of them. I wouldnt think I would need to enable something like this - but w/o a schematic I cant tell if there is a relay
involved or just a fuse.

I did see the ABS panel but inside it has nothing related to the trailer and no blue wire at all. Its just some small gauge stuff.

 

I actually opened the BLUE wire as it comes out of the frame rail and tested at that point to eliminate any other possibility....
Its dead...
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